Motor-compressor suspension



March 22, 1960 R. M GREGOR MOTOR-COMPRESSOR SUSPENSION Filed March 19, 1958 INVENT OR.

Ralf/l m 'reyor BY Q. Q/fl' HIS AT ORNEY MOTOR-COMPRESSOR SUSPENSION Ralph McGregor, Dayton, Ohio, assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application March 19, 1958, Serial No. 722,460

7 Claims. (Cl. 230-235) This invention relates to refrigerating apparatuses and particularly to the suspension in a sealed casing of a motor-compressor unit.

An object of my invention is to provide an improved and simplified suspended mounting of a motor-compressor unit in a sealed casing part of a closed refrigerating system.

Another object of my invention is to suspendingly support an operable means or unit such as a motorcompressor of a refrigerating system within a casing for movement relative thereto in several different directions and in a manner that will substantially reduce or eliminate transmission of noises and vibrations created by the unit to the casing.

A further object of my invention is to suspend a motor-compressor unit within a casing or support memher from a point at the top thereof whereby the unit nted States Patent will have up and down vibrational movement and swinging movement in pendulum fashion in all directions rela-' tive to the casing and also rotary movement therein certain of which movements are at times snubbed and limited in a novel manner. 7

In carrying out the foregoing object it is a still further and more specific object of my invention to provide in a casing a motor-compressor unit of the type including a vertically disposed hollow main substantially central bearing, about which the motor rotor and compressor driving shaft revolves, which bearing is unattached to the casing but is supported from the topthereof by a resilient means anchored to the lower end of the bearing and extending therethrough whereby the unit is floatingly mounted in the casing for pendulum swinging movement about the anchoring point of the resilient means to the bearing. 7

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

Figure 1 is a vertical sectional view through a motor compressor containing casing of a refrigerant compressing and liquefying portion of a refrigerating system; and

Figure 2 is a top view of the casing with a part thereof broken away to show certain elements within the casing.

Referring to the drawings, for illustrating my invention, I show in Figure 1 thereof a motor-compressor unit disposed in a casing which is usually located in the bottom of a refrigerator cabinet to form a part of a refrigerant compressing and liquefying portion of a closed refrigerating system associated with the refriger ator. The casing is hermetically sealed, is provided with refrigerant inlet and outlet connections as is conventional in the art and the unit therein is adapted to be started and stopped in response to refrigeration demands placed on the refrigerating system. The sealed casing includes an upper inverted cup-like metal housing 11' telescoped into and welded about its edges to a lower from and rests on the cast metal housing 18 by being secured to the collar 15. Rotor 16 is mounted on a shaft 22, which drives the compressor, surrounding and revolvable about a vertically disposed hollow bearing 23.

The upstanding bearing 23 is rigidly secured, by welding; or brazing, to a non-operating part of the motor-compressor unit such as the housing 18. Shaft 22 has an eccentric 24 formed on its lower end and surrounded by the connecting. rod 21 forreciprocating the compressor piston 19 within cylinder 17. A C-shaped clip 25 is clamped in a groove provided in bearing 23 adjacent its upper end to hold the motor rotor 16 on shaft 23 during assembly of the unit and to maintain such assembly while mounting the unit in the casing. The head of cylinder 17 is closed by plates provided with the usual refrigerant inlet and outlet valves (not shown), as is conventional in the art, and a muffler 26 communicates with the compressed refrigerant discharge or outlet valve port. While I disclose a reciprocating. type compressor or driven element it is to be understood that this element may, without departing from the realm of the invention, be a rotary type compressor or element.

According to my invention and in order to floating'ly support the operable means or motor compressor unit within the support member or sealed casing, for limited movement in all directions relative thereto, and so as to dampen the transmission of vibrations and noises to the outer casing I provide what is believed to be a new and unique mounting of the unit therein. A threaded support or stud 31 is welded to an inverted cup-like bumper means 32 which in turn is welded to the top wall of housing 11 of the sealed casing substantially centrally thereof. The lower portion of bumper 32 is shouldered as at 28 and flared outwardly and downwardly at 29 for a purpose to be hereinafter described. A resilient means or coil spring 33 has its upper coiled end anchored to the support or stud 31 at the top of the sealed casing by threading a plurality of the coils of the spring over or upon the threads of stud 31. Spring 33 has a coiled portion thereof disposed in the bore of hollow bearing 23 and projecting outwardly thereof through its upper open end. The lower end 34 of spring 33 is passed through a hole provided in a pin 36, fitted in a notch 37 cut in the lower end portion of bearing 23, and this end 34 of the spring is knotted or enlarged so that it cannot slip out of or away from pin 36. The feature of threading the coiled upper portion of spring 33 onto the threads of stud 31 provides a means of adjusting or varying the tension of the spring during assembly of the unit and also provides for up and down adjustment of the motor-compressor unit with respect to inverted cup-like housing 11 so as to properly locate the unit within the sealed casing. The feature of making the coiled portion of spring 33 of substantially the same outside diameter as the bore in bearing 23 together with disposing some of the coiled spring portion within the bearing bore and of projecting same outwardly of its open upper end provides the necessary stability between the motor-compressor unit and the sealed casing to suspendingly support the unit therein as herein disclosed. For example spring or resilient means 33 suspendingly supports percent of the weight of the at the top of the sealed casing and I provide other means Patented Mar. 22, 1960- which in addition to supporting the remainder percent of the weight of the unit also serves another purpose in the presently disclosed arrangement. To this end I weld clips 41 to opposed side walls of the cup-like housing portion 11 of the sealed casing and also weld a metal strap to the mufl ler 26. I stretch a spring 43 of a pair thereof between a clip 41 and an endof strap 42 and hook one end of the springs 43 to a clip 41 and their other end to an end of the strap (see Figure 2). Clips 41 are located at a slightly higher elevation than the strap 42 and thereby the springs 43 serve as an upward component for supporting the remainder 10 percent of the weight of the motor-compressor unit within the sealed casing. The springs 43 also form a means which restricts rotary movement of the operable means or motor-compressor unit within and with respect to the casing to a predetermined are as and for the purpose to be hereinafter more specifically described. Suspension of the motor-compressor unit within the sealed casing by a coiled spring extended through the main central bearing of the unit as herein disclosed is to be distin guished from supporting a unit or operating mechanism upon a plurality of spaced apart springs. In other words the present disclosure provides a floating support wherein swinging movement of a motor-compressor unit in pendulum fashion in all directions is obtained as distinguished from a pendulum swinging movement of a unit upon two spaced supporting means or springs in only opposite directions.

When the sealed casing is mounted in a refrigerator cabinet and connected in a closed refrigerating system associated therewith the motor of the motor-compressor unit in the casing is intermittently started and stopped automatically in response to refrigeration demands of the refrigerating system as is conventional and well-known to those skilled in the art. As the motor rotor 16 starts to be revolved, upon energizing the electric motor, and/ or as the same stops revolving, rotor 16 together with shaft 22 impart a torque force to the operable means or motor-compressor unit which tends to rotate same within and with respect to the sealed casing. This rotary movement of the motor-compressor unit about its resilient suspension with respect to the casing is restricted by either of the spring means 43 and limited to a predetermined arc. Thus rotary movement of the motor compressor unit within the sealed casing upon starting and stopping the motor thereof is snubbed in such a manner that the unit will not strike the casing and create a noise. The location and arrangement of the springs 43 is such that while they restrict rotation of the motorcompressor unit they do not interfere with or prevent a desired normal swinging movement of the unit in pendulum fashion within the sealed casing in all directions. The suspension of the motor-compressor unit as disclosed is such that operation of the motor rotor 16 during a running cycle of the unit may cause up and down vibrations and/or swinging movement of the unit relative to the sealed casing in pendulum fashion in all directions about the anchoring point of spring 33 to the lower end portion of bearing 23. These movements are not ordinarily objectionable since they do not, within limited range, create noises and transmit same to the outer metal casing. In fact such vibrational movement and normal swinging movement in pendulum fashion are desired and are specifically provided for in the floating unit suspension herein disclosed. Normal vibrational movements of the motor-compressor unit are taken up or absorbed by spring 33 and ordinary pendulum swinging movements of the unit are permitted during operation of the mechanism. While I have provided for normal vibrational movement and swinging movement in pendulum fashion of the motor-compressor unit within the'sealed casing during operation of the unit the structure disclosed also includes provisions for limiting these movements under abnormal conditions such as during shipment of a refrigerator cabinet with the sealed casing mounted therein. For example a sudden bump or jar in a downward direction of the sealed casing will cause the motor-compressor unit to quickly shift upward in the casing and a part of the motor rotor 16 will strike the lower flanged end portion 29 of bumper 32 whereby the bumper absorbs the shock and prevents damage to other portions of the motor-compressor unit such as the wire windings of the motor stator 14. Also a sidewise bump or jar of the sealed casing will cause an abnormal swing of the motor-compressor unit therein, in pendulum fashion about the anchoring point of spring 33 to the lower end of bearing 23, whereupon the free portion of spring 33, intermediate stud 31 and the upper end of bearing 23, will engage the shoulder 28 on the bumper 32 to resiliently absorb and limit the abnormal swing of the unit.

It should, from the foregoing, be apparent that I have provided a simplified and improved resilient floating suspension type of mounting for a motor-compressor unit of a refrigerating system within a sealed casing. In the improvement herein disclosed very little vibrations or noises, created by operation of the motor-compressor unit, are transmitted to its sealed casing. Also by this mounting and the use of the bumper means and the two snubber springs the motor-compressor unit is suspendingly supported in the sealed casing for normal vibrational movements and swinging movements in pendulum fashion in all directions therein during operation of the unit. The location and arrangement of parts within the sealed casing in addition to taking up or snubbing abnormal vibrations, bumps or jars during shipment or transportation of the casing in a refrigerator cabinet also holds or maintains the motor-compressor unit in its proper spaced position therein to provide a quieter and smoother operating mechanism after installation of the refrigerator. 7

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be,

understood that other forms might be adopted, as may come within the scope of the claims which follow.

What is claimed is as follows:

1. In combination, a sealed casing, a unit located in said casing including a motor, a compressor, a hollow upright bearing having its lower end stationarily secured to a part of said compressor and a shaft surrounding and revolvable about said bearing by said motor for driving the compressor, means mounting said unit within said casing, said means comprising opposed elastic members attached to said unit and connected to opposite sides of said casing and an element extending through said hollow bearing, said element having one of its ends fastened to a lower portion of said bearing in the vicinity of said part of said compressor and having its other ends anchored to the top wall of said casing in vertical alignment with the axis of said shaft, and said element being provided with a resilient section intermediate said ends thereof suspendingly supporting substantially the entire weight of said unit from said casing top wall for vibrational movement in the casing and for swinging movement relative thereto in pendulum fashion about said anchorage of the element to said casing.

2. The combination defined by claim 1 wherein the resilient section of the suspension element includes a coiled spring;

3. The combination defined by claim 1 wherein a bumper depends from the top Wall of the casing and extends around the resilient section of the suspension element for engagement thereby during pendulum swing ing movement of the unit to limit such movement thereof in all directions within said casing.

'4. In combination, a support,'means associated with said support including an operative member, an operable member, a hollow upright bearing having its lower end stationarily secured to a part of said operable member tion of said operable member and having its other end anchored to said support in vertical alignment with the axis of said shaft, and said element being provided with a resilient section intermediate said ends thereof suspendingly supporting substantially the entire weight of said members from said support for vibrational movement 'thereon and for swinging movement relative thereto in pendulum fashion about said anchorage of the element to said support.

5. The combination defined by claim 4 wherein the resilient section of the suspension element is in the form of a coiled spring. a

6. The combination defined by claim 4 wherein a bumper depends from the support and extends around the resilient section of the suspension element for engagement thereby during pendulum swinging movement of the members to limit such movement thereof in all directions.

7. In combination, a sealed casing, a unit located in said casing including a motor, a compressor, a hollow upright bearing having its lower end stationa-rily secured to a part of said compressor and a shaft surrounding and revolvable about said hearing by said motor for driving the compressor, means mounting said unit within said casing, said means comprising opposed elastic members attached to said unit and connected to opposite sides of said casing and a spring extending through said hollow bearing, said spring having one of its ends fastened to a lower portion of said bearing in the vicinity of said part of said compressor and having its other end anchored to the top wall of said casing in vertical alignment with the axis of said shaft, said spring having a coiled section abutting the inner wall surface of said hollow bearing and projecting outward of the open top thereof, said coiled section of the spring suspendingly supporting substantially the entire weight of said unit from said casing top wall for vibrational movement in the casing and for swinging movement therein relative thereto in pendulum fashion about said anchorage of the spring to said casing, a cylindrical bumper rigidly secured to said casing top wall and surrounding that part of the coiled section of said spring projecting out of said hollow bearing in spaced relation thereto, said bumper being engageable by the coiled section of said spring to limit the pendulum swinging movement of said unit in all directions within said casing, and a part of the motor of said unit being adapted to engage said bumper upon abnormal vibrations of the unit in said casing.

References Cited in the file of this patent UNITED STATES PATENTS Forsberg Nov. 19, 1935 Philipp July 30, 1957 OTHER REFERENCES 

